Applied Mathematical Modelling最新文献

{"title":"Inverse design of hydroacoustic absorbing metastructures via incorporating multi-material topology optimization into semi-analytical method","authors":"Shengsen Xu ,&nbsp;Yang Wang ,&nbsp;Lin Liu ,&nbsp;Fanyin Zeng ,&nbsp;Haibin Yang ,&nbsp;Jie Zhong ,&nbsp;Zhoufu Zheng ,&nbsp;Dianlong Yu ,&nbsp;Jihong Wen","doi":"10.1016/j.apm.2025.116265","DOIUrl":"10.1016/j.apm.2025.116265","url":null,"abstract":"<div><div>Hydroacoustic absorbing metastructures (HAMs), owing to their widespread application in underwater sensing and stealth, have attracted increasing interest during the last decades. Although intensely pursued, novel design paradigms for realizing broadband absorption and highly efficient analytical methods for accelerating the iteration of the design process remain to be proposed. This work proposes a new class HAM comprising a multi-material structure sandwiched into rubber layers. The multi-material structure consists of viscoelastic material, elastic material, and fine distributed pores, serving as the core that achieves the energy dissipation and the waveform conversion. A semi-analytical method (SAM), combining explicit expressions and a numerical homogenization process, is established to predict the absorption performance of the HAM. The proposed SAM is widely applicable for complex structural forms and is more computationally efficient than the conventional finite element method (FEM). An inverse design strategy for the HAM is subsequently proposed by incorporating the multi-material topology optimization into the SAM. Under different constraints, various HAMs achieving high sound absorption in the low-frequency and broadband are acquired, demonstrating the effectiveness of the inverse design strategy. The proposed analytical and design method can extend to other structural designs by considering multi-physics field coupling.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116265"},"PeriodicalIF":4.4,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A shape optimisation of mutual inductances among coils","authors":"Toru Takahashi,&nbsp;Tatsuya Tokito,&nbsp;Yi Cui,&nbsp;Toshiro Matsumoto","doi":"10.1016/j.apm.2025.116257","DOIUrl":"10.1016/j.apm.2025.116257","url":null,"abstract":"<div><div>This paper introduces a shape optimisation framework for achieving desired mutual inductances (MIs) among coils in 3D space. Utilising a wire modelling approach, the coils are discretised using B-spline curves, with control points (CPs) serving as design variables. The key contribution is the derivation of the shape derivative of the objective function in terms of MIs, enabling the use of gradient-based quasi-Newton optimisation methods. A coil length constraint is also incorporated. The study demonstrates the effectiveness of the framework through numerical examples, validating the theoretical and numerical developments. This approach addresses the largely unexplored area of magnetostatic MI optimisation within the wire modelling framework, offering a computationally efficient alternative to finite element methods etc.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116257"},"PeriodicalIF":4.4,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144296931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability analysis of slope heterogeneous traffic flow considering network attacks and driver continuous memory effects","authors":"Futao Zhang,&nbsp;Yujiao Chen,&nbsp;Yongsheng Qian,&nbsp;Junwei Zeng,&nbsp;Xin Li","doi":"10.1016/j.apm.2025.116263","DOIUrl":"10.1016/j.apm.2025.116263","url":null,"abstract":"<div><div>The heavy dependence of intelligent connected vehicles on communication systems renders them more susceptible to cyberattacks, which can compromise traffic flow stability and lead to potential system failures. In mountainous road environments, where infrastructure is often underdeveloped, communication shielding effects are prevalent, resulting in frequent signal interruptions and communication delays for connected vehicles. This study focuses on mountainous roads and develops a mixed traffic flow model comprehensively considering the incorporation of dynamic communication topologies under network attack scenarios, the limited communication range, the persistence of driving information memory, and the differences in information exchange between connected and manually driven vehicles. We calibrated the model parameters using 331 real-world trajectory datasets. The stability of homogeneous traffic flow was investigated using the reduced perturbation theory, which indicated that both the continuous memory effect and multi-vehicle information feedback positively enhance stability. A benchmark comparison with classical models revealed that the newly proposed connected vehicle following model significantly outperforms the Intelligent Driver Model, the Following Vehicle Departure Model, and the Gipps model in fitting real-world driving trajectories, achieving improvements of 51.65%, 25.88%, and 50.20%, respectively. Furthermore, the model exhibits superior speed control accuracy (root mean square error reduced by over 46.24%) and speed stability (as evidenced by a 48.28% reduction in standard deviation). For the diverse communication topologies associated with heterogeneous fleets, the stability criteria of such fleets were derived through the application of control transfer functions. Additionally, four distinct network information attack scenarios were established to simulate and analyze the impacts of information deception, delay, and collusion attacks on fleet driving dynamics. Research findings demonstrate that connected vehicles are effective in mitigating traffic flow fluctuations. Moreover, the distribution of vehicles' relative spatial positions significantly influences the propagation intensity of disturbances within traffic streams. Drivers with conservative driving behaviors tend to increase speed variations among vehicles, thereby affecting stability. The insights derived from this study can serve as a reference for developing strategies to manage traffic flow on mountainous highways and enhancing the integration of connected communication technologies into vehicle control systems.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116263"},"PeriodicalIF":4.4,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144305085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting jams in heterogeneous disordered traffic: Insights from tipping point theory","authors":"Shankha Narayan Chattopadhyay,&nbsp;Arvind Kumar Gupta","doi":"10.1016/j.apm.2025.116254","DOIUrl":"10.1016/j.apm.2025.116254","url":null,"abstract":"<div><div>Regime shifts, characterised by abrupt transitions, occur widely in complex systems, from ecosystem collapses and marine ice instability to traffic congestion and disease outbreaks. Statistical indicators with universal applicability, known as early warning signals, are key for predicting such critical transitions in advance. This study introduces an intriguing lattice hydrodynamic area occupancy model, incorporating vehicular passing effects, to explore the dynamics of heterogeneous traffic systems typical of emerging economies, where infrastructural constraints and a lack of lane discipline increase traffic complexity. The formation and evolution of kink and chaotic traffic jams are analysed through theoretical modelling and numerical simulations. A systematic framework employs generic statistical measures - including standard deviation, skewness, kurtosis, and lag-1 autocorrelation - to identify early indicators of impending congestion. A comprehensive sensitivity analysis of the indicators' processing parameters and evaluations of their significance and robustness are performed to ensure a more nuanced and insightful interpretation. Results reveal that the statistical measures' predictive performance is sensitive to the choice of moving window size and bandwidth of the smoothing function. Further, it is observed that the higher-order moments are more prone to yielding false negatives, irrespective of the traffic jam being kink-antikink type or chaotic. This work provides a robust basis for predictive methodologies to address congestion in highly heterogeneous environments, offering insights into the interplay between statistical indicators and phase transitions in complex transportation systems.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116254"},"PeriodicalIF":4.4,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Random vibro-acoustic analysis of thick laminated cylindrical shells under turbulent boundary layer via symplectic wave-based method","authors":"Jiaqi Mi ,&nbsp;Yongping Jiang ,&nbsp;Ruxin Gao ,&nbsp;Yuanyuan Li","doi":"10.1016/j.apm.2025.116252","DOIUrl":"10.1016/j.apm.2025.116252","url":null,"abstract":"<div><div>The symplectic wave-based method is developed for the random vibro-acoustic analysis of laminated cylindrical shells under turbulent boundary layer. First, based on the semi-empirical model of the turbulent boundary layer, the random vibration response of laminated cylindrical shells under turbulent boundary layer is transformed into the superposition of a series of steady-state response. Secondly, the governing equations for the vibration analysis of laminated cylindrical shells in the Hamiltonian system are established based on the first-order shear deformation theory, and the steady-state response of the laminated cylindrical shell is solved using wave propagation analysis in the symplectic system. Finally, the sound pressure spectrum inside the cylindrical shell cavity is obtained from the vibration response of the laminated cylindrical shell structure according to the Kirchhoff-Helmholtz integral. Compared to the modal decomposition method, the proposed method can analytically handle arbitrary boundary conditions with higher convergence speed and computational accuracy. Numerical examples validate the convergence and effectiveness of the proposed method, and the influence of axial pressure on the random vibro-acoustic response of laminated cylindrical shells is analyzed.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116252"},"PeriodicalIF":4.4,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144305089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitivity-based model updating with parameter rejection","authors":"Martin D. Ulriksen ,&nbsp;Dionisio Bernal","doi":"10.1016/j.apm.2025.116253","DOIUrl":"10.1016/j.apm.2025.116253","url":null,"abstract":"<div><div>Sensitivity-based model updating entails a computational parameter estimation problem, in which a set of model parameters is adjusted to minimize the discrepancy between identified system features and the corresponding model predictions. In order to promote the posedness and conditioning of the estimation problem, it is often necessary to exclude some of the uncertain parameters and accept the errors induced by treating them at their nominal values. The present paper proposes a parameter rejection scheme that seeks to mitigate the noted errors by minimizing the sensitivity of the estimation problem to changes in the excluded parameters. The sensitivity minimization is realized in a closed-loop setting with output feedback eigenstructure assignment, which, given that the operation is offline, can be implemented through processing of open-loop input-output data. Consequently, the scheme rests on the assumption that open-loop input-output data can be collected while the considered system is linear and time-invariant. The implementation and validity of the scheme are demonstrated in the context of numerical and experimental examples with vibrating systems.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116253"},"PeriodicalIF":4.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Balancing the trade-off between efficiency and equity in a stochastic emergency supplies allocation problem","authors":"Shihong Huang ,&nbsp;Hongyi Zhu ,&nbsp;Hongyuan Wang ,&nbsp;Kanglin Liu ,&nbsp;Xiaohang Liu ,&nbsp;Zhi-Hai Zhang","doi":"10.1016/j.apm.2025.116242","DOIUrl":"10.1016/j.apm.2025.116242","url":null,"abstract":"<div><div>Emergency supplies, including essentials such as food, water, tents, and medicines, often face shortages immediately following a disaster. Uneven distribution of these supplies can result in disparities in assistance, making equity a crucial objective in humanitarian logistics. Given the typically limited relief budgets, we add another objective that minimizes the total operational cost, which is composed of inventory and transportation costs. To achieve both goals simultaneously, this paper proposes a bi-objective programming model that aims to increase relief efficiency by minimizing the total operational cost while also capturing distribution equity through a quantitative index inspired by the Gini index. We develop a stochastic programming framework to account for demand uncertainty. The proposed nonlinear bi-objective two-stage stochastic programming model is transformed into a mixed-integer linear program via the <em>ϵ</em>-constraint method and a scenario-based approach. To address computational challenges, we implement a branch-and-cut-based L-shaped algorithm with several acceleration techniques. On the basis of an empirical case study focusing on the mask distribution process in Pudong New Area, Shanghai, our findings indicate the following: (i) the accelerated algorithm improves the computational efficiency; (ii) the proposed two-stage stochastic scheme outperforms its deterministic counterpart, and (iii) the proposed equity-promoting bi-objective model leads to a more diverse distribution.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116242"},"PeriodicalIF":4.4,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-dependent analysis model of soft rock tunnels incorporating yielding layer","authors":"Nannan Zhao,&nbsp;Ziyan Wang,&nbsp;Yuezong Yang,&nbsp;Zhushan Shao,&nbsp;Kui Wu","doi":"10.1016/j.apm.2025.116259","DOIUrl":"10.1016/j.apm.2025.116259","url":null,"abstract":"<div><div>The application of yielding layer provides a potential good solution to the problem of large deformation in deep soft rock tunnels. Previous researches on analysis models of tunnels incorporating yielding layer have certain limitations, as one model is only applicable to one type of yielding layer material. The purpose of this work is to establish a unified analysis model of tunnels considering the yielding layer effect in order to address the limitations of existing models. Firstly, the nonlinear stress-strain curve of yielding layer materials is partitioned and multiple straight line segments are employed to approximate the original curve. A mathematical expression for elastic moduli is provided to uniformly describe the deformation characteristics of different yielding layer materials. Secondly, the tunnel construction process is divided into three stages and a viscoelastic mechanical model of tunnels considering the yielding layer effect is established. Based on stress boundary and displacement continuity conditions, analytical solutions for tunnel displacement and interface contact stresses during different deformation stage are provided. The proposed model can be used to predict the mechanical performance of tunnels incorporating yielding layer materials with arbitrary compressive characteristics, and can degrade to some simpler tunnel cases. Furthermore, the reliability of this mechanical model is verified by comparing with the numerical calculation results. Finally, a comprehensive parametric investigation is carried out based on the analytical solutions. The analysis results indicate that the tunnel supporting effect is significantly affected by the mechanical properties of yielding layer materials, the yielding layer thickness and the deformation capacity of surrounding rock.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116259"},"PeriodicalIF":4.4,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144296930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional thermal and stress distributions in multi-material corners under thermo-mechanical loads","authors":"M. Pastrello ,&nbsp;M. Zappalorto","doi":"10.1016/j.apm.2025.116230","DOIUrl":"10.1016/j.apm.2025.116230","url":null,"abstract":"<div><div>In this paper, an analytical solution for the temperature and stress fields in the close neighborhoods of multi-material corners in thick plates under thermo-mechanical loads is presented. To this end, as a first step in the analytical treatment, the three-dimensional field equations are reduced to two uncoupled equations to be solved independently. Later, the 3D analytical description of the thermal and stress fields in the vicinity of multi-material corners under thermomechanical loads is presented and its degree of accuracy is discussed by comparing theoretical results and numerical data from 3D FE analyses.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116230"},"PeriodicalIF":4.4,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bayesian nonparametric estimation of differential entropy for toroidal data","authors":"Najmeh Nakhaei Rad ,&nbsp;Mohammad Arashi ,&nbsp;Andriette Bekker ,&nbsp;Sollie Millard","doi":"10.1016/j.apm.2025.116241","DOIUrl":"10.1016/j.apm.2025.116241","url":null,"abstract":"<div><div>Entropy is a widely used information-theoretic measure; however, the estimation of entropy for observations of a periodic nature has not received much attention thus far. In this paper, we implement a Bayesian approach to obtain nonparametric estimates of Shannon entropy for toroidal data. This paves the way for its use in protein structure validation through an approach based on information theory and the distribution of backbone dihedral angles in the 3D structure of proteins. In addition, the kernel density estimation proposed in this paper can be applied alongside available parametric models for modeling toroidal observations. Simulation studies and the analysis of real datasets provide insights into this proposed method for protein structure validation.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116241"},"PeriodicalIF":4.4,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144253631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}